Rock-drill



(No Model.)

BOOK DRILL- Patented Jan. 2, 1894.

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, w w w T' fifi W NQ Q N, w 1 9 $3 Nu A W w UNITED STATES ARTHUR E. BUZZO AND HENRY H. THOMPSON, OF ISHPEMING, MICHIGAN.

ROCK-DRILL.

SPECIFICATION forming part of Letters Patent No. 512,154, dated. January 2, 1894.

Application filed August 15,1893- Serial No. 483,195. (Nomodel-l i To ctZZ whom it may concern:

Be it known that we, ARTHUR E.BUZZO and HENRY H. THOMPSON, citizens of the United States, residing at Ishpeming, in the county of Marquette and State of Michigan,have invented certain newand useful Improvements in Rock-Drills; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and use the same.

Our invention relates to improvements in rock drills, and it consists of certain novel features hereinafter described and claimed.

Reference is had to the accompanying drawings, wherein the same parts are indicated by the same letters.

Figurel represents a plan view of the machine, the drill being broken away. Fig. 2 represents a vertical section along the line a; x of Fig. 1. Fig. 3 represents a plan View of the machine with the cover of the steam chest removed, and the valves taken out. Fig. 4 represents a section along the line y y of Fig. 2, looking in the direction of the arrows. Fig. 5 represents a section along the line 11 y of Fig. 2, looking in the direction of the arrows. Fig. 6 represents a section along the line 2 z of Fig. 2, looking in the direction of the arrows, and Fig. 7 represents a perspective view of the valves for admitting steam into the two ends of the cylinder, with the rocking arms for operating the same.

A represents the drill which is held in the chuck B, the said chuck being mounted on the piston rod 0, which is rigidly attached to the spool-shaped piston O'. This piston is provided with conical surfaces 0, connected together by the cylindrical portion 0, and the piston is packed by the packing rings 0 of the ordinary form of construction. The rear portion of the piston O is hollowed out to receive the end of the shaft 0 carrying the ratchet wheel 0 This shaft is provided with a plurality of spiral grooves 0 adapted to re ceive corresponding lugs or projections 0 on the interior of the piston. The pawls O pressed forward by springs c engage in the ratchet wheel 0 as shown in Fig. 6.

D represents the frame in which the piston and the steam chest are included. This frame or casting D contains the cylinder E, and the steam chest F, and is provided with journal bearings d and d for the rods 0 and C respectively, and with the chamber (1' to receive the ratchet wheel 0 The steam chest F is provided with valve chambers F and F and with chambers F in which the rocking arms H and H are mounted. The steam chest is connected to the cylinder by the ports ffor the admission of steam and for the exhaust, and by the passagesf" for the rocking arms H and H It is also connected with the sourceof pressure by the steam pipes G.

Steam or compressed air or any similar fluid under pressure, is intended to supply the requisite power.

The valves H and A are mounted on the same shaft H with the rocking arms 11 and H and the ports h and h in these valves are so arranged that steam will be admitted into one end of the cylinder while the other end of the cylinder is open to the exhaust.

The lower part of the steam chest is shown in detail in Fig. 3, in which f represents the bearings for the shaft or valve stem H, audio represents the exhaust passages opening into the exhaust pipes K and K situated at opposite ends of the cylinder.

The rocking arms H and H are represented as attached to the valve stem H by means of p the screws h but any convenient way of rigidly attaching these arms to the valve stem, may be adopted.

The operation of the device is as follows Suppose the various parts to be in the positions shown in Fig. 2, and steam orair pressure to be turned on to both of the pipes G. The steam will pass through the valve H and enter the cylinder in rear of the piston, while at the same time the opposite side of the piston is open to the exhaust. As the piston moves toward the front of the cylinder, the studs 0 engaging in the grooves 0 will cause theratchet wheel 0 to revolve beneath the pawls 0 while the drill A will deliver a straight blow. When the piston has advanced far enough to cause the inclined surface h of the rocking arm H to strike against the rear one of the conical surfaces 0, the valve stem H will be moved through a small angle by the wedging of this rockingarm up on the said conical surface, and the position of the valves will be so changed that the valve H will admit steam, and the valve II will be open to the exhaust. The piston will soon begin to move in the reverse direction,butin moving backward the pressure from the piston tending to revolve the ratchet wheel 0 will be resisted by the pawls C and since the lugs (2 must travel in the groove 0 the piston itself is caused to revolve through a small angle, thus giving the drill a small angular motion on the return stroke, and enabling it to strike a fresh part of the rock. As soon as the piston returns to the initial position shown in Fig. 2, the rocking arm H is tripped by the front conical surface 0, and another cycle of the apparatus begins. It will thus be seen that with a great simplicity of the operating parts a rapid reciprocating motion is obtained.

The spool shape of the piston not only combines the well known advantages of steam packing, and corresponding lightness of parts, but also renders it possible for the piston to operate the rocking arms H and II. This operation of the valves by the piston itself assists in rendering the machine compact;-and the peculiar shape of the piston and the various parts contiguous thereto insures a large space in the steam chest for the fluid under pressure.

It will be obvious that various modifications might be made,'which could be used without departing from the spirit of our invention.

Having thus described our invention, what We claim, and desire to secure by Letters Patent of the United States, is-

1. In a machine of thecharacter described,

, the combination of a cylinder, a piston movrigidly connected to said valves and engaging said inclined surfaces, substantially as and for the purposes described.

2. In a machine of the character described, the combination'with a cylinder of a spoolshaped piston moving therein; two valves controlling ports' opening into the two ends of said cylinder; a valve stem rigidly connected to each of said valves, and tripping arms connected to said valve stem and adapted to engage the inclined surfaces of said spool-shaped piston, substantially as and for the purposes described.

3. In a machine of the character described, the combination with a cylinder, of a spool shaped piston moving therein; two cylinder valves controlling ports opening into the two ends of said cylinder; a valve stem rigidly connected to each of the said valves; and tripping arms connected to said valve stem, and provided with curved ends adapted to engage said inclined surfaces, substantially as and for the purposes described.

In testimony whereof we affix oursignatures in presence of two witnesses.

ARTHUR E. BUZZO. HENRY H. THOMPSON.

Vitnesses:

E. J. GRAY, A. K. \SEDGVVICK. 

